Integrated display and capture apparatus

ABSTRACT

An integrated imaging apparatus for displaying images while capturing images of a scene, including an electronic display having an array of display pixels which are used to display image content; at least one image capture device which captures an image, wherein the image capture device having at least an imaging lens and an image sensor array; and wherein the image capture device looks through an aperture in the display, the aperture having at least one partially transparent pixel; and wherein the partially transparent pixels also provide light to display image content.

CROSS REFERENCE TO RELATED APPLICATIONS

Reference is made to commonly assigned U.S. patent application Ser. No.11/341,945 filed Jan. 27, 2006, entitled “EL Device Having ImprovedPower Distribution” by Ronald S. Cok et al; U.S. patent application Ser.No. ______ filed concurrently herewith, entitled “An Integrated DisplayHaving Multiple Capture Devices” by Ronald S. Cok et al and U.S. patentapplication Ser. No. ______ filed concurrently herewith, entitled “TwoWay Communication System” by Ronald S. Cok et al, the disclosures ofwhich are incorporated herein.

FIELD OF THE INVENTION

The present invention relates to apparatus for two-way communication ofimages and in particular relates to an integrated capture and displayapparatus that provides both image display and image capture functions.

BACKGROUND OF THE INVENTION

Two-way video systems are available that include a display and camera ineach of two locations connected by a communication channel that allowscommunication of video images and audio between two different sites.Originally, such systems relied on setup at each site of a video monitorto display a remote scene and a separate video camera, located on ornear the edge of the video monitor, to capture a local scene, along withmicrophones to capture the audio and speakers to present the audiothereby providing a two-way video and audio telecommunication systembetween two locations.

Referring to FIG. 1, a typical prior art two-way telecommunicationsystem is shown wherein a first viewer 71 views a first display 73. Afirst image capture device 75, which can be a digital camera, capturesan image of the first viewer 71. If the image is a still digital image,it can be stored in a first still image memory 77 for retrieval. A stillimage retrieved from first still image memory 77 or video imagescaptured directly from the first image capture device 75 will then beconverted from digital signals to analog signals using a first D/Aconverter 79. A first modulator/demodulator 81 then transmits the analogsignals using a first communication channel 83 to a second display 87where a second viewer 85 can view the captured image(s).

Similarly, second image capture device 89, which can be a digitalcamera, captures an image of second viewer 85. The captured image datais sent to a second D/A converter 93 to be converted to analog signalsbut can be first stored in a second still image memory 91 for retrieval.The analog signals of the captured image(s) are sent to a secondmodulator/demodulator 95 and transmitted through a second communicationchannel 97 to the first display 73 for viewing by first viewer 71.

Although such systems have been produced and used for teleconferencingand other two-way communications applications, there are somesignificant practical drawbacks that have limited their effectivenessand widespread acceptance. Expanding the usability and quality of suchsystems has been the focus of much recent research, with a number ofproposed solutions directed to more closely mimicking real-lifeinteraction and thereby creating a form of interactive virtual reality.A number of these improvements have focused on communication bandwidth,user interface control, and the intelligence of the image capture anddisplay components of such a system. Other improvements seek tointegrate the capture device and display to improve the virtual realityenvironment.

There have been a number of solutions proposed for addressing theproblem of poor eye contact that is characteristic of many existingsolutions. With conventional systems that follow the pattern of FIG. 1,poor eye contact results from locating the video camera on a differentoptical axis than the video monitor and causes the eyes of an observedparticipant to appear averted, which is undesirable for a videocommunication system. Traditional solutions for addressing this problem,employing a display, camera, beam splitter, and screen, are described ina number of patents, including U.S. Pat. No. 4,928,301 entitled“Teleconferencing terminal with camera behind display screen” to Smoot;U.S. Pat. No. 5,639,151 entitled “Pass-through reflective projectiondisplay” and U.S. Pat. No. 5,777,665 entitled “Image blockingteleconferencing eye contact terminal” to McNelley, et al.; and U.S.Pat. No. 5,194,955 entitled “Video telephone” to Yoneta et al., forexample. Alternately, commonly assigned U.S. Patent ApplicationPublication No. 2005/0024489 entitled, “Image capture and displaydevice” by Fredlund et al. describes a display device for capturing anddisplaying images along a common optical axis. The device includes adisplay panel, having a front side and a back side, capable of beingplaced in a display state and a transmissive state. An image capturedevice is provided for capturing an image through the display panel whenit is in the transmissive state. An image supply source provides animage to the display panel when it is in the display state. A mechanismis also provided for alternating placing the display panel between thedisplay state and the transmissive state, allowing a first image to beviewed and a second image to be captured of the scene in front of thedisplay at high rates such that alternating between the display stateand the transmissive state is substantially imperceptible to a user.

Commonly assigned U.S. Pat. No. 7,042,486 entitled, “Image capture anddisplay device” to Manico et al. describes an image capture and displaydevice that includes an electronic motion image camera for capturing theimage of a subject located in front of the image display device and adigital projector for projecting the captured image. An optical elementprovides a common optical axis electronic camera and a light valveprojection screen electronically switchable between a transparent stateand a frosted state located with respect to the common optical axis forallowing the electronic camera to capture the image of the subjectthrough the projection screen when in the transparent state and fordisplaying the captured image on the projection screen when in thefrosted state. A controller, connected to the electronic camera, thedigital projector, and the light valve projection screen, alternatelyplaces the projection screen in the transparent state allowing theelectronic camera to capture an image and in the frosted state allowingthe digital projector to display the captured image on the projectionscreen. This system relies on switching the entire display devicerapidly between a transparent and a frosted state. However, with manytypes of conventional imaging components, this can induce image flickerand result in reduced display brightness. Furthermore, the single cameraused cannot adjust capture conditions such as field of view or zoom inresponse to changes in scene.

Although such solutions using partially silvered mirrors and beamsplitters have been implemented, their utility is constrained for anumber of reasons. Solutions without a common optical axis provide anaverted gaze of the participant that detracts from the conversationalexperience. Partially silvered mirrors and beam splitters are bulkyparticularly in the depth direction. Alternately transparent orsemi-transparent projection display screens can be difficult toconstruct and with rapid alternation between states, ambient contrastcan suffer and flicker can be perceptible. As a number of thesesolutions show, this general approach can result in a relatively bulkyapparatus that has a limited field of view and is, therefore, difficultfor the viewer to use comfortably.

As an alternative approach, closer integration of image display andsensing components has been proposed. For example, U.S. PatentApplication Publication No. 2005/0128332, entitled “Display apparatuswith camera and communication apparatus” by Tsuboi describes a portabledisplay with a built-in array of imaging pixels for obtaining an almostfull-face image of a person viewing a display. The apparatus describedin the Tsuboi '8332 disclosure includes a display element in whichdisplay pixels are arranged, along with a number of aperture areas thatdo not contain display pixels. In its compound imaging arrangement,multiple sensors disposed behind the display panel obtain a plurality ofimages of the scene through a plurality of clustered lenses that aredisposed over aperture areas formed among the display pixels. Eachsensor then converts the sensed light photo-electrically to obtain aplurality of tiny images of portions of the scene that are then piecedtogether to obtain a composite image of the scene. To do this, thedisplay apparatus must include an image-combining section that combinesimage information from the plurality of images obtained by using thecamera.

As another variation of this type of compound imaging approach, U.S.Patent Application Publication No. 2006/0007222, entitled “Integratedsensing display” by Uy discloses a display that includes displayelements integrated with image sensing elements distributed along thedisplay surface. Each sensing pixel may have an associated microlens. Aswith the solution proposed in the Tsuboi '8332 disclosure, compoundimaging would presumably then be used to form an image from theindividual pixels of light that are obtained. As a result, similar tothe device in the Tsuboi '8332 disclosure, the integrated sensing devicedescribed in the Uy '7222 application can both output images (e.g., as adisplay) and input light from multiple sources that can then be piecedtogether to form image data, thereby forming a low-resolution cameradevice.

Similarly, U.S. Patent Application Publication No. 2004/0140973,entitled “System and method of a video capture monitor concurrentlydisplaying and capturing video images” by Zanaty describes an apparatusand method for compound imaging in a video capture monitor that uses afour-part pixel structure having both emissive and sensing components.Three individual emissive pixel elements display the various Red, Green,and Blue (RGB) color components of an image for display of informationon the video-capture monitor. Additionally, as part of the same pixelarchitecture, a fourth pixel element, a sensing element, captures aportion of an image as part of a photo-electronic array on the videocapture monitor. Although this application describes pixel combinationsfor providing both image capture and display, however, the difficulty inobtaining image quality with this type of a solution is significant andis not addressed in the Zanaty '0973 disclosure. As an example of justone problem with this arrangement, the image capture pixels in the arrayare not provided with optics capable of responding to changes in thescene such as movement.

The compound imaging type of solution, such as proposed in the examplesof the Tsuboi '8332, Uy '7222, and Zanaty '0973 disclosures, is highlyconstrained for imaging and generally falls short of what is needed forimage quality for the captured image. Field of view and overall imagingperformance (particularly resolution) are considerably compromised inthese approaches. The optical and computational task of piecing togethera continuous image from numerous tiny images, each of which may exhibitconsiderable distortion, is daunting, requiring highly complex andcostly control circuitry. In addition, imaging techniques using an arrayof imaging devices pointed in essentially the same direction tend toproduce a series of images that are very similar in content so that itis not possible to significantly improve the overall image quality overthat of one of the tiny images. Fabrication challenges, for formingmulti-function pixels or intermingling image capture devices withdisplay elements, are also considerable, indicating a likelihood of lowyields, reduced resolution, reduced component lifetimes, and highmanufacturing costs.

A number of other attempts to provide suitable optics for two-waydisplay and image capture communication have employed pinhole cameracomponents. For example, U.S. Pat. No. 6,888,562 entitled, “Integraleye-path alignment on telephony and computer video devices using apinhole image sensing device” to Rambo et al., describes a two-wayvisual communication device and methods for operating such a device. Thedevice includes a visual display device and one or more pinhole imagingdevices positioned within the active display area of the visual display.An image processor can be used to analyze the displayed image and toselect the output signal from one of the pinhole imaging devices. Theimage processor can also modify the displayed image in order to optimizethe degree of eye contact as perceived by the far-end party.

In a similar type of pinhole camera imaging arrangement, U.S. Pat. No.6,454,414 entitled “Device for image output and input” to Ting describesan input/output device including a semi-transparent display and an imagecapture device. To be semi-transparent, the display device includes aplurality of transparent holes. As yet another example, U.S. Pat. No.7,034,866 entitled “Image-sensing display device with particular lensand sensor arrangement” to Colmenarez et al. describes an in-plane arrayof display elements alternating with pin-hole apertures for providinglight to a camera.

The pinhole camera type of solution, as exemplified in the Rambo et al.'562, Ting '414, and Colmenarez et al. '866 disclosures suffer fromother deficiencies. Images captured through a pinhole reflect lowbrightness levels and high noise levels due to low light transmissionthrough the pinhole. Undesirable “screen door” imaging anomalies canalso occur with these approaches. Display performance and brightness arealso degraded due to the pinhole areas producing dark spots on thedisplay. Overall, pinhole camera solutions inherently compromise bothdisplay image quality and capture image quality.

As just indicated, a structure of integrated capture pixels intermingledin a display may cause artifacts for either the image capture system orthe image display performance. To some extent, the capture pixelstructures can be thought of as defective pixels, which might becorrected or compensated for by appropriate methods or structure. As anexample, European Patent Application EP1536399, entitled “Method anddevice for visual masking of defects in matrix displays by usingcharacteristics of the human vision system” to Kimpe, describes a methodfor reducing the visual impact of defects present in a matrix displayusing a plurality of display elements and by providing a representationof a human vision system. The Kimpe EP1536399 disclosure describes atleast one defect present in the display deriving drive signals for atleast some of the plurality of non-defective display elements inaccordance with the representation of the human vision system,characterizing the at least one defect, to reduce an expected responseof the human vision system to the defect, and then driving at least someof the plurality of non-defective display elements with the deriveddrive signals. However, a display having an occasional isolateddefective pixel is a different entity than a display having a deliberatesub-structure of intermingled capture aperture or pixels. Thus thecorrective measures to enhance display image quality can besignificantly different.

One difficulty with a number of conventional solutions relates to aninability to compensate for observer motion and changes in the field ofview. Among approaches to this problem have been relatively complexsystems for generating composite simulated images, such as thatdescribed in U.S. Patent Application Publication No. 2004/0196360entitled “Method and apparatus maintaining eye contact in video deliverysystems using view morphing” by Hillis et al. Another approach to thisproblem is proposed in U.S. Pat. No. 6,771,303 entitled“Video-teleconferencing system with eye-gaze correction” to Zhang et al.that performs image synthesis using head tracking and multiple camerasfor each teleconference participant. However, such approaches side-stepthe imaging problem for integrated display and image capture devices byattempting to substitute synthesized image content for true real-timeimaging and thus do not meet the need for providing real-lifeinteraction needed for more effective video-conferencing andcommunication.

The proliferation of solutions proposed for improved teleconferencingand other two-way video communication shows how complex the problem isand indicates that significant problems remain. Thus, it is apparentthat there is a need for a combined image capture and display apparatusthat would allow natural two-way communication, provide good viewer eyecontact, adapt to different fields of view and changes in scene content,provide good quality capture images with reduced artifacts, and providea sufficiently bright display without noticeable defects in thedisplayed image.

SUMMARY OF THE INVENTION

In accordance with this invention, there is provided an integratedimaging apparatus for displaying images while capturing images of ascene, comprising:

a) an electronic display having an array of display pixels which areused to display image content;

b) at least one image capture device which captures an image, whereinthe image capture device includes at least an imaging lens and an imagesensor array; and

c) wherein the image capture device looks through an aperture in thedisplay, the aperture having at least one partially transparent pixel;and wherein the partially transparent pixels also provide light todisplay image content.

The present invention provides an apparatus comprising an integratedimage display and image capture device that provide improved capturecapability and improved display image quality. In addition, using thesolution of the present invention, image capture conditions can bechanged in response to changes in the scene.

BRIEF DESCRIPTION OF THE DRAWINGS

In the detailed description of the preferred embodiments of theinvention presented below, reference is made to the accompanyingdrawings in which:

FIG. 1 is a block diagram of a typical prior art telecommunicationsystem;

FIGS. 2A and 2B are perspective views showing an apparatus in accordancewith the present invention, operating in a display mode and in an imagecapture mode, respectively.;

FIG. 3 shows a timing diagram for image display and image capture forthe present invention;

FIG. 4 is a perspective of an image capture device as used in thepresent invention;

FIG. 5 is a cross section of one embodiment of the present invention;

FIG. 6 is a more detailed cross section of the embodiment of FIG. 5;

FIG. 7 is a cross section of an alternative embodiment of the presentinvention having transparent thin-film electronic components;

FIG. 8 is a cross section of a further embodiment of the presentinvention having a plurality of transparent display pixels;

FIG. 9 is a cross section of another embodiment of the present inventionhaving a plurality of transparent display pixels of a common color;

FIG. 10 is a cross section of yet another embodiment of the presentinvention having adjacent transparent portions;

FIG. 11 is a top view of the embodiment of FIG. 10;

FIG. 12 is a cross section of an alternative embodiment of the presentinvention having common light-emitting materials and color filters;

FIG. 13 is a cross section of an additional embodiment of the presentinvention having an electrode with reflective and transparent portions;

FIG. 14A is a top view of a further embodiment of the present inventionhaving multiple transparent portions and image capture devices;

FIG. 14B is a top view of a display of the present invention depictingvarious exemplary groupings of the semi-transparent pixels;

FIG. 15 is a cross section of an alternative embodiment of the presentinvention having Fourier plane spatial filtering;

FIG. 16 is a block diagram showing system components of the presentinvention in one embodiment;

FIG. 17 is a top view showing system components of the present inventionin one embodiment; and

FIG. 18 is a block diagram showing system components of the presentinvention in a networked embodiment.

DETAILED DESCRIPTION OF THE INVENTION

The apparatus and method of the present invention address the need foran integrated display and image capture device by taking advantage of acombination of factors including the following:

(i) fabrication of display device components of various types havingsubstantially transparent electrode materials;

(ii) use of light modulation components that can be alternately emissive(or absorptive or reflective) and transparent;

(iii) timing to synchronize alternating image capture and image displayfunctions for various apparatus components;

(iv) structural device layout and design to enhance image capture andimage display; and

(v) corrective methods to enhance image quality for image capture andimage display.

Significantly, the apparatus and method of the present invention avoidthe pitfalls of compound imaging, as was described earlier withreference to the examples of the Tsuboi '8332, Uy '7222, and Zanaty'0973 disclosures by using imaging optics and sensor components, ratherthan merely using sensors that detect light and attempting to assemblean image by tiling or other image synthesis methods. In addition, theapparatus and method of the present invention avoid problems typicallyassociated with pinhole imaging, as was described earlier with referenceto the Rambo et al. '562, Ting '414, and Colmenarez et al. '866disclosures. This is because the apparatus and method of the presentinvention utilize transparency properties of various types of displaycomponents to provide a suitable aperture for imaging, withoutsignificant detriment to display image quality.

It should be noted that drawings used to show embodiments of the presentinvention are not drawn to scale, but are illustrative of key componentsand principles used in these embodiments. Moreover, it must beemphasized that the apparatus of the present invention can be embodiedin a number of different types of systems, using a wide variety of typesof supporting hardware and software.

FIGS. 2A and 2B show an important feature of operation that is utilizedby the apparatus and method of the present invention. An integrateddisplay and capture apparatus 100 of the present invention generallyincludes a display 5 and one or more capture devices 40. Display 5 hasan arrangement of pixel elements or pixels 8 and 9 that form a displayscreen that is observed by one or more viewers (not shown). Displaypixels 8, shown shaded in FIGS. 2A and 2B, are conventional displaypixels, such as emissive OLED pixels or transmissive LCD pixels. Pixels9, shown white or clear in FIGS. 2A and 2B, also act as display pixels,but are fabricated and controlled to be at least partially transparent,and are thus termed as at least partially transparent (orsemi-transparent) display pixels 9 in the present application. Capturedevice 40 is nominally a digital or video camera having a lens 42 fordirecting light toward an image sensor 41 for capturing a plurality ofimage pixels. In the depiction of FIG. 2A, at least partiallytransparent pixels 9 are in a display mode, contributing a portion ofdisplay image light 62. Pixels 9 either emit light (for an OLED display)or transmit (or reflect) light (for an LCD display). In the depiction ofFIG. 2B, at least partially transparent pixels 9 are in a transparentmode or clear mode, and receiving incident light 60 from a distantscene. The timing chart of FIG. 3 shows a display timing pattern 102 forat least partially transparent pixels 9 and a capture timing pattern 104for capturing an image from the image sensor 41. A frame time (Δt) isspanned by one full cycle through ON and OFF states (an exemplary 50%duty cycle is shown). When the at least partially (in time) transparentpixels 9 are in a clear or transparent state, an image capture cycle canbe executed, as is shown in FIG. 2B. When the at least partiallytransparent pixels 9 are in a display state, nominally no image capturetakes place. The timing patterns (106 a,b,c) for the operation of thedisplay pixels 8 will be discussed subsequently.

As is shown in FIG. 4, the capture device 40 includes imaging opticswith an optical axis 43. The basic components of capture device 40 arethe lens 42 and an image sensor 41, optionally encased in a housing 44(shown in dotted lines in FIG. 4). Image sensor 41 has an array ofsensor pixels 45, arranged in rows 46 and columns 47, as is well knownin the imaging arts. Incident light 60, represented by dotted lines, isdirected toward image sensor 41 by lens 42 to form an image thereon.Baffles (not shown) internal to lens 42 can be provided to minimize anystray light or ghost images from degrading the image capture. Lens 42can employ folded optics the thickness of the housing. Image sensor 41can capture an image having a large number of pixels. Image sensor 41 islikely a CCD or CMOS sensor array, having a resolution of ˜1-8megapixels. The image that is captured can be a full scene image or aportion or tile of a larger, composite image. Unlike many of thedisplay/capture device solutions of earlier approaches that attempt tocapture a single pixel using a sensor optically coupled to a lenslet,the use of an image sensor 41 in the present invention acts as a cameraand provides a two-dimensional image from each capture device 40.

As noted earlier, transparency of display components at least duringimage capture is an important attribute for their implementation in theintegrated display and capture device 100 of the present invention.Subsequent figures and description outline a number of embodiments usingthis principle with image sensor 41 and employing the timing andsynchronization described with reference to FIGS. 2A, 2B, and 3.

Referring to FIG. 5, one embodiment of an integrated display and thecapture apparatus 100 according to the present invention includesdisplay 5 having a plurality of display pixels 8 wherein one or more ofthe display pixels 8 is at least partially transparent (as shown by atleast partially transparent display pixel 9 in FIG. 5) and partiallyopaque (as shown by display pixels 8 in FIG. 5). Capture device 40 hasan image sensor 41 for capturing a plurality of image pixels, asdescribed earlier with reference to FIG. 4.

Display 5 has a first side 6 from which it is viewed. Capture device 40is located on a second side 7 opposite the first side 6, in a positioncorresponding to the location of the at least partially transparentdisplay pixel 9. Capture device 40 receives light 60 from the scene onfirst side 6 through at least partially transparent pixel 9 to form animage of the scene. In one embodiment of the present invention, display5 is formed on a substrate 10 and includes a cover 20 adhered to thesubstrate 10 for protecting the display 5. The first side 6 from whichthe display is viewed can be the cover 20 side; second side 7 can be thesubstrate 10 side and the capture device 40 located adjacent tosubstrate 10, with light emitted through cover 20. Alternately, capturedevice 40 can be located on cover 20 side with light emitted from thesubstrate 10 side. In one embodiment of the present invention, displaypixels 8 include a reflective electrode 12 and a common transparentelectrode 16. Display pixels 8, which can be either monochrome or colorpixel, emit light in a forward direction (towards a display viewer),with the back-emitted light re-directed forwards by the reflectiveelectrode 12. The semi-transparent pixel 9 that is at least partiallytransparent can include two transparent electrodes 16 and 13. As shown,there is a particular type of display pixel 8, which is a white lightemitter 14W, which includes a semi-transparent pixel 9 and a portionwith a thin film electronic component 30. Thin film electroniccomponents 30 can be electrodes, transistors, resistors, or other basiccircuitry components.

As the term is employed herein, a partially transparent pixel is onethat transmits sufficient light to form an effective image when viewedor recorded by a capture device 40. For apparatus of the presentinvention, at least 50% transparency is needed and better than 80%transparency is preferred. Transparency is possible by virtue of devicedesign and composition. For example, OLED devices, because they usethin-film components, can be fabricated to be substantially transparent,as has been described in the article “Towards see-through displays:fully transparent thin-film transistors driving transparent organiclight-emitting diodes,” by Gorrn et al., in Advanced Materials, 2006,18(6), 738-741. Typically, the patterned materials are deposited in thinfilms (e.g. 100 nm thick) that are effectively transparent. In the caseof an OLED display, display pixels 8 can include a layer 14 of patternedorganic materials 14R, 14G, 14B that emit red, green, or blue lightrespectively. In the case of a monochrome display, display pixels 8 andsemi-transparent pixels 9 can both emit white light. OLED devices arewell known in the display imaging arts.

Another alternative for providing transparency is using LCD displaytechnology. Where display 5 is an LCD display, layer 14 includesswitchable liquid crystals that switch between a transparent and alight-absorbing state. Reflective and transparent electrodes are knownin the art and can include, for example, metals and metal oxides such asreflective aluminum or silver layers and transparent indium tin oxideconductors. Transparent electrodes can also be somewhat reflective,formed, for example, from thin layers of silver. LCD devices aresimilarly well known in the display imaging arts. In particular, thegeneral architecture of a trans-reflective LCD, in which the pixels haveboth reflective and transmissive portions could be extended to create anintegrated display and capture device.

As shown in FIG. 5, transparent display pixel 9 forms an aperture A inthe display screen through which image sensor 41 obtains light 60. Thesize of aperture A, or window, through which one or more capture deviceslook, is an important factor for the performance of the system.Optically, it is desirable that the size of the aperture A be as largeas possible. An aperture A should be large enough (for example, >25 μm)that significant diffraction effects are not imparted to the light 60 insuch a way that the image formed by the capture device 40 would bedegraded. Increasing the size of aperture A increases the opticalthroughput of the light 60 available to a capture device 40, enabling abrighter image with less noise. Larger effective apertures A with lessintervening structure will also help lens focusing, as there will beless “screen door effect” to confuse the lens. Also, as it is difficultto make small cameras having optical components such as lens 42 andimage sensor 41, it is preferred to make the aperture A as large aspossible.

For the apparatus and method of the present invention, the relationshipof aperture A to pixel size is important. As is well known, pixel sizecan vary significantly between devices. In some large-format displaydevices, the pixel size can be on the order of 0.05 to 1 mm² in area. Inparticular, current cell phone displays typically have pixels that are˜0.1-0.2 mm wide, while computer monitors use ˜0.3 mm wide pixelstructures, and large panel entertainment systems have 0.5-0.8 mm widepixel structures. Embodiments described subsequently outline approachesfor arranging pixels in such a way as to maximize aperture A as well asto compensate for inherent problems in obtaining a sufficiently sized orsufficiently transparent aperture A. For example, for the displays 5 ofFIGS. 7, 8, and 10, the effective aperture size A is increased withpixel structures in which regions of transparency are expanded bygreater use of semi-transparent materials (such as ITO electrodes) orpixel patterning to enhance aperture adjacency. In other cases (FIGS. 9and 15), the effective aperture A is increased by having image capturedevices 40 look through multiple offset transparent pixels (9). However,it should be noted that the design of these apertures A ofsemi-transparent pixels (or ensembles thereof), including their size andpatterning, needs to be designed with consideration for their visibilityas potential display artifacts for a display user. Nominally the capturedevice 40 is aligned to be centered and normal (optical axisperpendicular to) an aperture A, unless it is deliberately askew,including being tilted or panned to track motion.

According to another embodiment of the present invention for anintegrated display and capture apparatus 100, display pixels 8 areactive-matrix pixels that include thin-film electronic components 30 tocontrol the light emission or reflection of the display pixels.Referring to FIG. 6, display 5 has thin-film electronic components 30are formed on substrate 10. Planarization layers 32 and 34 are employedto smooth layer surfaces and provide insulation between layers andbetween electrodes 12 and 13 formed in a common layer. In oneembodiment, the thin-film electronic components are formed on relativelyopaque silicon. Electrode 13, within aperture A, is transparent. Emittedlight 62 can be provided from both transparent and opaque pixels.

Referring to the embodiment of FIG. 7, display 5 has thin-filmelectronic components are formed of one or more transparent materials,for example zinc oxide or doped zinc oxide, and indium tin oxide (ITO).As an example, light 60 can pass through any thin-film electroniccomponents 30 which are “relatively transparent”, such as partiallytransparent electrodes 30 a, to be incident upon image sensor 41. Thus,the size of semi-transparent pixels can effectively be expanded, therebyincreasing the aperture A size and improving the performance of thecapture device 40.

In FIG. 8, the capture device 40 receives light 60 through multipledisplay pixels 8 and 9 of display 5, thereby increasing aperture A. Inthe example shown, some amount of light is obtained from the imagedscene through the portion of light emitting pixel 14W, includingsemi-transparent pixel 9, and further light from the portion with apartially transparent electrode 30 a. Image light is also collectedthrough at least a portion of green color pixel 14G, which is partiallytransparent layer of green patterned organic 14G material in an OLEDdevice. The aperture A can be expanded further by providing othercolor-emitting pixels with a partially transparent electrode 30 ainstead of a nominally opaque electrode (30). Likewise, the partiallytransparent electrode 30 a of pixel 14W can be of the light blockingvariety (30). Even so, the effective aperture A is still increased, asincident light 60 passes through both the semi-transparent pixelportions of the white pixels (9) and the color pixels. Of course, anysemi-transmissive color pixels that are also functioning as windows forimage capture should be off (not light emitting) during the capturetime. Various other spatial arrangements of partially transparentdisplay pixels 9 can be employed, with filtered or non-filtered lightdirected toward image sensor 41, as is described subsequently.

FIG. 9 shows another embodiment for apparatus 100 in which light isobtained through an aperture A that comprises a plurality of offset orspaced apart window pixels that are interspersed among the displaypixels. In FIG. 9, the depicted light transmitting or window pixels areonly at least partially transparent display pixels 9. In thisembodiment, all of at least partially transparent display pixels 9 emitthe same color light, white in this case. However, the spaced apartlight transmitting pixels could be both white and color pixels,distributed individually or in clusters, to form aperture A. Since, witheither OLED or LCD devices, different colors can have different lightemission efficiencies, it can be useful to group commonly-coloredtransparent pixels to reduce differences between the differently coloredpixel groups. In particular, white emitters can be more efficient thanother colors. Using this improved efficiency can help to mitigate thevisual impact of employing a non-reflective electrode.

As another alternative embodiment for integrated display and imagecapture apparatus 100, shown in FIG. 10, the effective aperture A can beincreased beyond that available through a single partially transparentdisplay pixel 9 by fabricating the display 5 with the partiallytransparent display pixels 9 clustered or adjacent. In these cases, thecapture device 40 can be larger and can thus receive more light,possibly increasing the signal of image sensor 41. Reflected pixellayouts can be arranged to accomplish this as taught in commonlyassigned, above cited U.S. Ser. No. 11/341,945. Referring to FIG. 11, atop view of a portion of display 5 having such an arrangement is shown.Here, the component layout employs a bus connector 31, thin-filmtransistors 30 b, and at least partially transparent pixels 9 locatedadjacent to each other to form an increased aperture A generallyindicated by the dashed oval.

In an OLED embodiment of the present invention employing patternedorganic materials to form light emitters, the organic materials do notsignificantly absorb light that passes through the at least partiallytransparent display pixels 9. In an LCD embodiment, the liquid crystalsare likewise substantially transparent. In these embodiments, thecapture device 40 can employ additional color filters to form a colorimage of the scene on the first side 6 of the display 5.

Referring to FIG. 12, there is shown an OLED embodiment of the presentinvention employing unpatterned organic materials 14 to form broadbandlight emitters together with color filters 24R, 24G, and 24B to form acolor display. In this embodiment, the color filters 24R, 24G, and 24Bcan significantly absorb light that passes through them, providing acolored image to capture device 40. If an RGBW configuration isemployed, the white emitter does not have any color filter. If capturedevice 40 is located in alignment with such a white pixel with no colorfilters, then the capture device 40 will not receive colored light.Hence, the capture device 40 can form a monochrome or a color imagerecord without the need for separate color filters on image sensor 41.An optional black matrix 22 can be employed to reduce ambientreflection. The color filters 24R, 24G, and 24B can be located on theelectrode as shown in FIG. 12 or on the inside of the protective cover20 as shown in FIG. 7.

Referring to FIG. 13, reflective electrode 12 of display 5 can have areflective area 12 a and a transparent area 13 a through which lightpasses to capture device 40. In particular, for top-emitter structuressuch as is shown in FIGS. 5, 7, 8, and 10, a portion of the bottomelectrode is formed over areas corresponding to thin film electroniccomponents 30 such as thin-film transistors, and another portion isformed for the areas between these thin-film components (transistors(30)). In such instances, it can be useful to provide the reflectivearea 12 a above the areas corresponding to thin-film transistors (30)and the transparent area 13 a for the areas between the thin-filmtransistors (30). In this way, the use of emitted light is maximized.Such an electrode structure can be formed by providing a reflective,possibly conductive layer in the reflective areas 12 a only and atransparent layer over both the reflective areas 12 a and thetransparent areas 13 a as shown in FIG. 13.

In operation, the display 5 is controlled to emit or control light thatforms a display image on the first side 6 of the display 5, as was shownin FIG. 5. Ambient light 60 that illuminates a scene on the first side 6is incident on the display 5, passes through the one or moresemi-transparent display pixels 9, and is sensed by image sensor 41 ofcapture device 40 to form an image of the scene on the first side 9. Asshown in FIG. 14 a, integrated display and capture apparatus 100 can beequipped with one or more capture devices 40 that look through thedisplay 5. This plurality of capture devices (cameras) 40 can havedifferent imaging attributes, either individually or in combination.Most likely, these devices use lenses that have different focal lengths,and image with different fields of view (such as wide angle andtelephoto) or magnifications. A lens for one camera 40 can have zoomcapability, while the other lenses do not. These cameras 40 can havedifferent numbers of pixels (different sensor resolutions), differentspectral sensitivities of the light-sensing elements, different colorfilters, and other varying attributes. Some of these cameras 40 can bemounted with means (not shown) to facilitate pan and tilt functionality,to enable motion tracking in the user/viewer scene environment. Thus,the plurality of capture devices 40 can be directed to look at differentparts of a scene, in an overlapping or a non-overlapping manner. Animage processor 120 can output either multiple images or multiple imagedata (video) streams, or composite images or composite image streams. Acontroller 122 could facilitate both automatic and manual control of thevariable features (zoom, pan, tilt, changing field of view, changingscene brightness, etc . . . ) of the capture devices 40 to respond tochanging scene conditions.

As shown in FIG. 15, the capture device 40 can include a spectral filter66 somewhere prior to image sensor 41. Depending on the application,spectral filter 66 could be a band pass or band rejection filter. Forexample, spectral filter 66 could be a filter that transmits red andinfrared light (600-1200 nm, for example) while rejecting ultraviolet,blue, green, and out of band infrared light. As another option, spectralfilter 66 could be a filter that preferentially transmits ultravioletlight. In such cases, the associated image sensor 41 will also needsufficient sensitivity in the chosen spectral range. Those skilled inthe art will recognize that in the case wherein the capture device 40 isdesigned to operate in extreme low light conditions, it is beneficial toeliminate the spectral filter 66 to allow as much light as possible toreach the image sensor 41.

In addition, it should be noted that in certain cases where it isdesirable to produce images with light from outside the visible spectrum(350-700 nm), it is within the scope of the invention to add one or morecapture devices 40 that operate outside the visible spectrum such as inthe ultraviolet or the infrared. In these cases, it is important toselect a lens 42 that will operate in the ultraviolet (below 350 nm) orinfrared (above 700 nm) regions. A spectral filter 66 can be used toeliminate light outside the region that is to be imaged. The inventionalso anticipates the need for capture devices 40 operating inside thevisible spectrum to be combined with capture devices 40 operatingoutside the visible spectrum to enable sequential or simultaneousmulti-spectral imaging.

It is recognized that the integrated display and capture apparatus 100of the present invention, including a display 5 with display pixels 8and at least partially transparent pixels 9, as well as one or morecapture devices 40, can be subject to image artifacts in either theimage display or image capture spaces. These potential artifacts includespatial frequency effects, “screen door” effects, pin hole “defect”effects, stray and ghost light issues, color or spectral effects,flicker effects, and non-uniform shading issues. These artifacts (andothers), which can occur individually or in combination, can generallybe reduced with appropriate hardware designs or image processingcorrections, which can likewise be applied individually or incombination. In general, the goal would be to reduce the presence of anyimage display or image capture artifacts to at least just below theappropriate threshold for human perception thereof, thereby enhancingthe image quality. As will be seen, the hardware design and the imageprocessing can both be tailored to meet these needs.

As one example, FIG. 15 illustrates an integrated display and captureapparatus 100 that has baffles 64 to reduce image artifacts for bothimage display and image capture. Incident light 60 passes throughsemi-transparent pixels 9 or display pixels 8, and miss a given imagecapture device 40. That light could enter the capture device 40 aftervarious reflections and scattering events, and create ghost images orflare light, reducing image quality for either the displayed or capturedimages. Capture device 40 can have an external housing 44 and internalbaffles (not shown) that reduces this risk. Additionally, some incidentlight could re-emerge from behind the display 5, through transparentpixels and display pixels 8, and provide ghosts or flare light into theimages seen by a viewer of the display. To counter this, integrateddisplay and capture apparatus 100 is equipped with one or more lightabsorbing baffles 64, which can include coated plates and surfaces,sheet polymer materials, or light trapping structures. Baffles 64 can beformed on either side of substrate 10 of display 5. It is noted thatbaffles 64, which are similar to a backing for display 5, are generallydistinct from any thin film light absorbing layers that might beprovided within the display micro-structure to reduce unintended strayreflections from incoming ambient light. With respect to FIG. 14 a,these baffles would be located behind display 5, in the regions at leastbetween the various image capture devices 40. Of course, ifsemi-transparent pixels 9 are provided only in camera locations (seeFIG. 14 a), then baffles 64 may not be needed, or may only be need inproximity to apertures A.

The integrated structure of integrated display and capture apparatus 100can cause various capture image artifacts, including shadowing. Forexample, some portion of the light incident on image sensor 41 may havebeen occluded by thin-film electronic components 30 in the optical path.In this case, the capture device 40 records a scene with shadows imagedon image sensor 41. Such shadows can have a regular, periodic structure.Since these shadow areas are out of focus and are caused by a known partof the fixed optical structure of the digital capture device-displaysystem, the effects of the shadows on the image can be modeled, tested,and compensated. Compensation techniques for ambient lighting conditionsand for artifacts in the optics such as occlusions of the optical pathare known and can be implemented in an image post-processing step. Thisstep can be performed, for example, at image processor 120, as shown inFIG. 18.

The structure of display 5 can also cause other capture image defects,as image content is transmitted differently, removed, or obscured by thedevice structure. For example, in the case of the FIG. 8 embodiment, alight-transmitting aperture A can span portions of semi-transparentpixels 14W both with and without partially transparent electrodes 30 a,as well as portions color emitting pixels (such as 14G) that can also bepartially transparent, again either with or without partiallytransparent electrodes 30 a. As these different partially transparentpixels or pixel portions can have different transmittances in at leastthe blanking state, then the transmittance across an aperture A willvary spatially across the display 5. As long as the objects in thecaptured scene are sufficiently distant from the display, thesetransmission variations should be averaged out for all field points. Butas the objects become closer, these spatial variations in an aperture Aof display 5 could lead to image non-uniformities. These differences canbe most readily corrected or compensated for by the image processor 120.Likewise, if the incident light 60 passes through a color filter (24R,24G, or 24B—see FIG.7), the image that is obtained at image sensor 41can be adjusted to compensate for the filtering to correct spatial colorvariations in the image.

As another example, periodic spatial structures in display 5 can causecapture image artifacts, where image content is removed, or obscured oraltered by the effective frequencies of the structure. In some cases,optical compensation or correction techniques could be used. Inparticular, Fourier plane spatial filtering can be used to reduce thevisibility of artifacts caused by regular periodic structures. As anexample, an integrated display and capture apparatus 100 is depicted inFIG. 15, where display 5 has a repeating structure of red, green, blueand white pixels. Capture device 40, which includes a lens 42 withmultiple lens elements 42 a, 42 b and 42 c and an image sensor 41, looksthrough a multitude of semi-transparent pixels 9. Depending on the sizeof the lens 42 and the size and pitch of the semi-transparent pixels 9,the capture device 40 can be looking through several, or severalhundreds or more, of semi-transparent pixels 9 that are separated bycolor (or monochrome) pixels. Relative to the capture device 40, imagingthrough this array of apertures formed by the semi-transparent pixels 9can be much like imaging through a screen door, with a consequent lossof light intensity and the distraction of the structure itself, whichcan make focusing difficult, as well as impacting the image quality ofscenes with similar spatial frequencies. Aliasing could also occur.These semi-transparent pixels 9 can include white pixels (as in FIGS. 9,10, and 11), as well as semi-transparent structures where light istransmitted through nominally transparent electronic components(aperture A of FIG. 7) and/or through semi-transparent patterned colorpixel structures (aperture A of FIG. 8).

When the multitude of pixel semi-transparent pixels (9) are spatiallyrepeated in a periodic manner, or even a quasi-periodic manner, a staticstructure can occur in frequency space. In the case of an opticalsystem, this frequency structure is evidenced in the Fourier plane of alens system. For example, as shown in FIG. 15, capture device 40includes image sensor 41 and lens 42 with multiple lens elements (42 a,42 b, and 42 c). Within this optical system, a Fourier plane 68 exists,at, or in proximity to, an aperture stop 69. Incident light 60, which isincident from multiple locations in the field of view, is collectedthrough semi-transparent pixels 9 and focused or converged towards theFourier plane 68 (shown by a dashed line) and an aperture stop 69, whereafter multiple lens elements 42 b and 42 c create images on image sensor41. Most easily, spatial filtering with a fixed pattern Fourier planefilter 70 can reduce the fixed or static spatial frequency patternscreated by a display structure. For example, this filter can include a(two-dimensional) spatial pattern of highly absorbing regions formed ona transparent substrate, which is mounted between the multiple lenselements 42 a, 42 b and 42 c.

The distribution or pattern of semi-transparent pixels 9 and apertures Acan also create display image artifacts that could affect the displayviewer. In designing display 5, there is a choice whether pixels 9 andapertures A occur only where the plurality of capture devices 40 reside(per FIG. 14 a) or are across larger areas, and even the entire display5. As these at least partially transparent pixel 9 structures can befairly large (˜0.1-1.0 mm for a linear dimension) and patterned, theycan create visible artifact that irritate the display user. For example,within an area with a pattern with different display intensities, theuser can perceive a “banding effect”, where the structures appear as anartifact with a several mm pitch that aligns with regions of maximalhuman spatial pattern sensitivity. The pattern of semi-transparent pixelstructures can also create a speckled appearance to the display thatcould annoy the viewer. For example, in extremum, the pattern of windowor transparent pixels could seem like a grid of dark spots (in either aclear/transparent or dark state). This is illustrated in FIG. 14 b, inwhich different pixel groupings (26 a, 26 b, 26 c) of semi-transparentpixels 9 are shown, and pixel groupings 26 a and 26 b represent regulargrids. If the pixels 9 are small enough, they might exist generallyun-noticed. However, as an example, the traverse of a displayed motionimage across the display could increase their perceptibility for aviewer.

There are various approaches that can be used to reduce the visibilityof the semi-transparent pixels 9 (or apertures A) for the displayviewer. To begin with, the semi-transparent pixels 9 can only befabricated where cameras will be located, and not across an entiredisplay. The semi-transparent pixels 9 (white) can also be smaller thanthe RGB pixels. However, as it is desirable to locate a camera behindthe display, at or near the screen center, for the purpose of “eyecontact” image capture for teleconferencing applications, furthermitigating design features may be needed. The semi-transparent pixels 9might be kept patterned in the same pitch within a row, but be staggeredacross rows, to appear less like a regular grid (less like pixelgrouping 26 a). As another approach, display 5 could have theintermingled semi-transparent pixels 9 (or apertures A) distributedquasi-periodically (pseudo-periodically) or randomly within a captureaperture of the capture device 40, or more broadly, across differentregions of the display 5, to reduce this effect. These concepts areexemplified by the illustrated pixel grouping 26 c of FIG. 12 b.However, as electronic devices, and array electronic devices inparticular, are conventionally fabricated with predefined repeatingstructures, random pixelization would be quite difficult. Aquasi-periodic structure is more likely, which could be either identicalor non-identical in the XY directions (horizontal and vertical of FIG.14 b) of a display 5. In optical frequency space (Fourier plane 68) forimage capture, a quasi-periodic pattern of pixels 9 could create afrequency pattern with gaussian profiles. Fourier plane filter 70 couldthen have a spatial patterned absorbance that followed a functionaldependence (such as a gaussian) in one or more locations, rather thanthe more traditional pattern of constant high absorbance (orreflectance) regions. Alternately, or in addition, frequency filteringto remove structural display artifacts from the image capture could bedone in the capture image processing electronics. The virtue of opticalfiltering, as compared to electrical/software filtering, is that itoccurs without requiring any computing power for data processing.

It can also be desirable to reduce the visibility of thesemi-transparent pixels 9 for image capture by modulating these pixelstemporally. In a sense, the timing diagram (FIG. 3) would be morecomplex, as the modulation within a frame time (Δt) would could bestaggered (out of phase) or segmented from one pixel 9 to another. Thismodulation could change the apparent spatial pattern or frequency ofthese pixels as perceived by a viewer, whether the display 5 includesgroupings (26) of semi-transparent pixels 9 that were periodically orquasi-periodically arrayed. In turn, that could affect the spatialfrequency pattern seen at the Fourier plane 68. Conceivably, Fourierplane filter 70 could be a dynamic device, such as a spatial lightmodulator (such as an LCD or DMD) that was temporally modulated insynchronization with the modulation of pixels 9. However, suchsynchronized frequency space corrections are likely best handleddirectly in the image processor 120 that handle the captured images.

The existence of semi-transparent pixels 9 or apertures A can causenon-uniformity artifacts (in addition to flare) that will impact thedisplayed image, depending on whether these pixels appear dark orbright. The spatial distribution and size of semi-transparent pixels 9across display 5 very much affects these artifacts. Some of these issuesare resolved if the dark state of semi-transparent pixels is a conditionof both no light emission and no light transmission. However, there arestill cases where display pixels 8 surrounding or adjacent to each ofthe semi-transparent pixels 9 (or apertures A) can be modulated in acalibrated compensating way to reduce the visibility of thesemi-transparent pixels 9 to a viewer of the display. The display scenecalibration can be undertaken in a scene dependent way, using the factthat the display electronics has information on the (static) structureof display 5, has control of the pixel modulation timing and intensity,and can pre-process the image to be displayed. For example, when asemi-transparent pixel 9 is in a white state in an area where agenerally bright whitish image is being displayed by the color pixels,the proximate display pixels 8 could be darkened to compensate.Likewise, when a semi-transparent pixel 9 (which can only be clear,dark, or white) resides in a displayed screen area of constant colorcontent (say red), the adjacent display pixels 8 could be brightened tocompensate for this pixel (as compared to red display pixels 8 furtheraway from a semi-transparent pixel 9). In another sense, thesemi-transparent pixels 9 might be used for display image contrastenhancement, given that they can be driven to either clear (dark) orwhite states.

The application of local or adjacent display pixels 8 to compensate orcorrect for the operation of a semi-transparent pixel 9, depends on howthe display pixels are operated. For example, if non-transparent lightemitting display pixels are on or emitting light during most of a frametime Δt, then they are in operation for some portion (see display timingpattern 106 b of FIG. 3) of the clear state for image capture for asemi-transparent pixel 9. The timing of display and capture is then atleast somewhat de-coupled, although the defined frame time Δt ispresumed constant. Local changes in display pixel brightness can beattained by providing an average constant intensity or by activelychanging the intensity within a frame time (display timing patterns 106c of FIG. 3). Thus, adjacent or proximate display pixels neighboring asemi-transparent pixel 9 could be driven higher when that pixel switchesclear (for example, if the ensemble of proximate color pixels give awhite image) or lower or left constant depending on the scene content.If the ON or light emission state timing for the non-transparent lightemitting display pixels is comparable to that of the semi-transparentpixels 9 (display timing pattern 106 a˜semi transparent pixel timingpattern 102), then pixel brightness differences probably can likely onlybe compensated via differences in display pixel intensity withouttemporal manipulation. This is particularly true for devices of the FIG.8 variety, where at least some display pixels 8 have transparentelectrode structures rather than reflective electrode structures. Inthat case, those pixels should follow the same nominal timing diagram(pattern 106 a=pattern 102, per FIG. 3) as the semi-transparent pixels9, so that they do not back emit light towards a capture device 40.

Likewise, on a larger scale, and considering again FIG. 14 a, display 5can be fabricated with semi-transparent pixels 9 or apertures A inplaces where capture devices 40 are present, or across the entiredisplay 5. In either case, whether these window pixels are across theentire display (suggesting the use of the baffles 64) or only in regionslocalized for cameras 40, the displayed images could look different inthe capture regions versus the non-capture regions. In particular, therecan be large areas with a different display appearance than other largeareas (that is, large spatial non-uniformities). By and large, thesemacro-non-uniformities should be anticipated and correctable (perhapswith the help of a calibration step) in the image processing electronics120, and compensated for in advance of image display.

However, the primary purpose of semi-transparent pixels 9 is to act aswindows or apertures for image capture by one or more cameras 40. For anOLED type device, these pixels can be driven to an “ON”, light emittingstate, to reduce their visibility to a display viewer. But all thepixels within a cameras field of capture nominally need to be “OFF” ortransparent for a sufficient time period that a nominally uniform imagecapture can occur over the capture field of view. Relative to thesemi-transparent pixel timing pattern 102 (FIG. 3), the display statedefinition of a dark pixel can be key. Generally, it is intended that adark semi-transparent pixel 9 is still ON or in a display state, anddoes not transmit light to a capture device 40. However, with somedesigns or device technologies for display 5, a dark state can equate toan OFF/clear state, in which case incident light 60 can be transmittedto the capture device 40. For example, that could mean that asemi-transparent pixel might be left in its clear or transparent state(dark state for the display viewer) for a prolonged period of time(relative to the capture frame time), if it resides in an image regionthat is dark for a prolonged time period. Light would then be incidentto the capture device (camera) 40 during the previously defined blankstate. Capture device 40 could have a shutter (not shown) to eliminatethis concern. Alternately, a spatially and/or temporally variantcorrection or gain adjustment might be made for the captured image asthe prolonged dark semi-transparent pixels 9 within a cameras field ofcapture will have much more light transmission in time than the pixelsthat are reaching ON states.

As was described with reference to FIG. 3, the simplest form of periodiccontrol can be to switch the semi-transparent pixels 9 off (clear) forsome portion of time to allow the capture device to capture the scene.Since, nominally, only the at least partially transparent display pixels9 are switched rather than all of the pixels, the switching can beunobtrusive in the display. Moreover, the image capture can be made in ashort portion of a period of time (e.g. 1/100^(th) of a second or aportion of a single frame at 30 Hz) reducing both the duty cycle forimage capture and the visibility of temporal artifacts. The operation ofnon-transparent light emitting display pixels is at least somewhatlinked to the operation of the semi-transparent pixels 9. For example,if they follow the same timing (pattern 106 a=pattern 102), thenreducing the off state time means that the same pixel intensity can beattained with less drive loading. Then, if a display pixel (8 or 9) isswitched off for 50% of the time while image capture occurs, the displaypixel can emit twice the light during the remaining 50% of the timeduring which the display pixel is switched on. As the time required forimage capture lengthens, it becomes more desirable (relative to flickerand instantaneous loading) to decouple the operation of thenon-transparent light emitting display pixels from the operation of thepixels comprising a semi-transparent aperture A.

Another image artifact, flicker, can affect both image display and imagecapture devices. In this case, by employing at least partiallytransparent display pixels 9 that switch between a non-active(transparent for image capture) and an active (ON) state, while thedisplay pixels are active (emitting or reflecting) during most of theframe time, flicker is reduced relative to the image display. Since onlythe display pixels having at least partially transparent areas areswitched between active and non-active states, the visual effect of theswitching on the display quality is reduced and the user experience isimproved. Admittedly, having display pixels on during image capturemeans that some display light can encounter objects in the capture fieldof view and reflect or scatter back towards the capture devices 40. Thislight could raise the noise floor, change the spectrum, or temporallyalter the captured images. However, the effects of this return light arelikely minimal compared to the ambient lighting. Moreover, electricaltechniques like supplying clocking or carrier frequency signals could beused to reduce such effects. In the case that the display andsemi-transparent pixels (white or color) follow the same timing diagram,it can be desirable to reduce the capture time (smaller duty cycle) orincrease the frame rate, to reduce flicker perceptibility.

As previously mentioned, back-emitted light (white or color) from thedisplay 5, for example in an OLED embodiment, with the reflectiveelectrodes replaced by transmissive electrodes, can be incident on imagesensor 41. This issue can largely be addressed by only emitting lightfrom these window pixels with matched timing patterns 102 and 106 a ofFIG. 3. Additionally, capture device 40 can be equipped with asynchronized light blocking shutter or sensor drains. Alternately, itcan be desirable to extend image capture (timing pattern 104″) to occurwhile image display is occurring. That is, the window pixels(semi-transparent pixels 9 and semi-transparent color pixels (per FIG.8)) of an aperture A would emit light (both forwards and backwards)during at least a portion of image capture. As the display controller122 knows the light 60 emitted by the display 5, the light emission fromthe display 5 can be subtracted from the light signal received by imagesensor 41 to improve the quality of image capture of the scene. Asanother option, the light emitted by the at least partially transparentdisplay pixel 9 can be periodically reduced during simultaneous imagecapture by image sensor 41 to improve the image capture of the scene. Inembodiments relying upon controllable light absorption to form an image(e.g. in an LCD), the amount of light absorbed by the partiallytransparent display pixel 9 is likewise known to a display controllerand a correction can be made to the corresponding image sensors tocorrect for the absorption of ambient light by the partially transparentdisplay pixel 9.

The prior discussions concerning the impact the structure of theintegrated display and capture apparatus 100 on the quality of imagecapture and image display has principally focused on the embodimentsintegrated display and capture apparatus 100 is an OLED type device andwhere at least partially transparent pixel 9 is then a light emittingpixel. However, as was previously discussed, integrated display andcapture apparatus 100 can also be a LCD type device. Even so, many ofthe previously discussed image artifacts, such as shadowing, flarelight, spatial pattern frequency effects, spectral transmissiondifferences, can affect the quality of the image capture. Likewise, manyof the previously discussed image display artifacts, such as pixelpattern perception and local and macro brightness differences, canaffect the quality of the image display. Thus, many of the varioushardware remedies (quasi-periodic pixel patterning, baffles, Fourierplane filtering, etc . . . ) and image processing remedies (pixelbrightness changes, shadow removal, gain and offset adjustments, etc . .. ) can be applied to the LCD case to reduce the presence of such imageartifacts.

It is also worth considering how the integrated display and captureapparatus 100 of the present invention interacts with a network,particularly given its potential use for telecommunications. Again, forcontext, FIG. 1, presents a typical prior art two-way telecommunicationsystem is shown wherein the first viewer 71 views the first display 73.A first image capture device 75, which can be a digital camera, capturesan image of the first viewer 71. In the present invention, the displayand capture apparatus will be much more highly integrated than isimplied by FIG. 1. Thus, FIG. 16 shows, in block diagram form, anintegrated display and capture apparatus 100 within part of acommunications network. A viewer 80 looks at display 5 that includes anintegrated digital capture device 40. Capture device 40 obtains an imagesignal, as described subsequently, and provides the image signal to animage processor 86 that provides the image data for transmission toanother site through a modulator 82. A demodulator 84 provides thecontrolling signals from the other site for operating display 5. Theblock diagram of FIG. 17 shows a top view of integrated display andcapture apparatus 100 in an alternate embodiment having a control logicprocessor 90 and a communications module 92 for providing the imagealong a network 94 or 96.

The block diagram of FIG. 18 shows a two-way communication system 110that utilizes an integrated capture device and a display, forcommunication between a viewer 80 a at a first site 112 and a viewer 80b at a second site 114. Each viewer 80 a, 80 b has an integrated imagecapture and display apparatus (100) comprising a display 5 with one ormore integrated capture devices 40. A central processing unit (CPU) 116coordinates control of the image processor 120 and the controller 122that provides display driver and image capture control functions. Acommunication control apparatus 124 acts as interface to a communicationchannel, such as a wireless or wired network channel, for transferringimage and other data from one site to the other. In the arrangement ofFIG. 17, two-way communication system 110 is optimized to support videoconferencing. Each viewer 80 a, 80 b is able to see the other viewerdisplayed on display 5 at that site, enhancing human interaction forteleconferencing. Image processing electronics 120 potentially servemultiple purposes, including improving the quality of image capture atthe local display 5, improving the quality of images displayed at thelocal display 5, and handling the data for remote communication (byimproving the image quality, data compression, encryption, etc.). Itmust be noted that FIG. 18 shows a general arrangement of componentsthat serve one embodiment. Capture devices 40 and display 5 areassembled into a frame or housing (not shown) as part of the deviceintegration. This system housing can also encompass the image processor120, controller 122, CPU 116, and communication control 124. Also notshown are audio communications and other support components that wouldalso be used, as is well known in the video communications arts.

In summary, the present invention provides an effective user experienceas the capture device and display are naturally integrated in amechanically thin package. In particular, the use of at least partiallytransparent display pixels 9 as opposed to pinholes formed in thedisplay improves the fill factor or aperture ratio of the display,enabling more of the display area to emit or reflect light, therebyimproving life times and display image quality. Display resolution canalso be improved. Moreover, the use of at least partially transparentdisplay pixels 9 with the capture device 40 located behind the at leastpartially transparent display pixels 9 allows the remainder of thedisplay area to be reflective or light absorbing, thereby improving theamount of light output or reflected or improving the ambient contrast ofthe display, improving display image quality as a result. Formingmultiple transparent areas improves the image capture capability byincreasing the light available to capture devices 40 located behind thetransparent areas or enabling a plurality of capture devices 40 to beemployed.

The integrated display and capture apparatus 100 of the presentinvention certainly has potential application for teleconferencing orvideo telephony. Additionally, this device might be used as aninterpretive display for advertising or as an interactive display forvideo games and other entertainment formats. The displayed image contentcan include photographic images, animation, text, charts and graphs,diagrams, still and video materials, and other content, eitherindividually or in combination. In particular, the integrated captureand display apparatus 100 could be used to capture an image of one ormore display users and then insert their images, in part or in total,into the displayed image content. Other applications for integrateddisplay and capture apparatus 100, in areas such as medical imaging, canbe considered. Integrated display and capture apparatus 100 can be sizedfor cell phone or handheld applications, or for use in a laptop ordesktop computer, or for use in an entertainment display. Integrateddisplay and capture apparatus 100 can also be equipped with integratedlight emitting devices for the purpose of illuminating a scene, whichcan be useful if the ambient lighting is low, or an unusual capturespectrum is desired. For example, the illuminating devices might beplaces around the outer edges of display 5. Likewise, other opticalsensing or detection devices could be substituted for image sensor 41 inone or more capture devices 40 used with an integrated display andcapture apparatus 100. For example, a low resolution wide angle lens anda quad cell, with simple sum and differencing electronics, could be usedto track motion, such as recognizing that someone has entered thecapture field of view. A specialized device, such as an opticalfingerprint imager could be provided, as a security feature.Alternately, single cell sensors could be used to detect ambient lightlevels or function as a photovoltaic cell for solar energy conversion.Most basically, an optical sensor needs to generate a useful electricalsignal in response to incident light.

The present invention can be employed in display devices. Such displaydevices can also include additional layers or optical devices, forexample protective or encapsulating layers, filters, and polarizers e.g.circular polarizers. In a preferred embodiment, the present invention isemployed in a flat-panel OLED device composed of small molecule orpolymeric OLEDs as disclosed in but not limited to U.S. Pat. No.4,769,292, issued Sep. 6, 1988 to Tang et al., and U.S. Pat. No.5,061,569, issued Oct. 29, 1991 to VanSlyke et al. Many combinations andvariations of organic light-emitting displays can be used to fabricatesuch a device, including both active-matrix and passive-matrix OLEDdisplays having either a top-emitter or bottom-emitter architecture.Other display device technologies can also be used in the presentinvention, including devices based on inorganic phosphorescentmaterials, such as quantum dots.

The invention has been described in detail with particular reference tocertain preferred embodiments thereof, but it will be understood thatvariations and modifications can be effected within the spirit and scopeof the invention. It should be understood that the various drawing andfigures provided within this invention disclosure are intended to beillustrative of the inventive concepts and are not to scale engineeringdrawings.

PARTS LIST

-   A aperture-   5 display-   6 first side-   7 second side-   8 display pixels-   9 at least partially transparent display pixel (or semi-transparent    pixel)-   10 substrate-   12 reflective electrode-   12 a reflective area-   13 transparent electrode-   13 a transparent area-   14 organic layer-   14R red patterned organic material-   14G green patterned organic material-   14B blue patterned organic material-   14W white patterned organic material-   16 transparent electrode-   20 cover-   22 black matrix-   24R red color filter-   24G green color filter-   24B blue color filter-   26 pixel groupings-   26 a pixel grouping-   26 b pixel grouping-   26 c pixel grouping-   30 thin-film electronic components-   30 a partially transparent electrodes-   30 b thin film transistors-   31 bus connector-   32 insulating planarization layer-   34 insulating planarization layer-   40 capture device (or camera)-   41 image sensor-   42 lens-   42 a lens element-   42 b lens element-   24 c lens element-   43 optical axis-   44 housing-   45 pixel-   46 row-   47 column-   60 light-   62 light-   64 baffle-   66 spectral filter-   68 Fourier plane-   69 Aperture stop-   70 Fourier plane filter-   71 first viewer-   73 first Display-   75 first image capture device-   77 first still image memory-   79 first D/A converter-   80 viewer-   80 a viewer-   80 b viewer-   81 first modulator/demodulator-   82 modulator-   83 first communication channel-   84 demodulator-   85 second viewer-   86 image processor-   87 second display-   89 second image capture device-   90 control logic processor-   91 second still image memory-   92 communications module-   93 second D/A converter-   94 network-   95 second modulator/demodulator-   96 network-   97 second communication channel-   100 integrated display and capture apparatus-   102 semi-transparent pixel timing pattern-   104 capture timing pattern-   106 a display timing pattern-   106 b display timing pattern-   106 c display timing pattern-   110 two-way communication system-   112 site-   114 site-   116 central processing unit (CPU)-   120 image processor-   122 controller-   124 communication control apparatus

1. An integrated imaging apparatus for displaying images while capturingimages of a scene, comprising: a) an electronic display having an arrayof display pixels which are used to display image content; b) at leastone image capture device which captures an image, wherein the imagecapture device having at least an imaging lens and an image sensorarray; and c) wherein the image capture device looks through an aperturein the display, the aperture having at least one partially transparentpixel; and wherein the partially transparent pixels also provide lightto display image content.
 2. The apparatus of claim 1 wherein theaperture is formed by a plurality of partially transparent pixels. 3.The apparatus of claim 2 wherein the plurality of partially transparentpixels is patterned contiguously to form the aperture.
 4. The apparatusof claim 2 wherein the plurality of partially transparent pixels arepatterned to form the aperture, such that at least a portion of thepartially transparent pixels are offset from one another, with at leastone of the display pixels located in an intervening space.
 5. Theapparatus of claim 2, wherein the plurality of partially transparentpixels is patterned, either individually or in clusters, in a periodicor quasi-periodic manner.
 6. The apparatus of claim 2, wherein theplurality of the partially transparent pixels is patterned in groups toform multiple apertures, with the partially transparent pixelspatterned, either individually or in clusters, in a periodic orquasi-periodic manner within the groups.
 7. The apparatus of claim 6,wherein baffles for blocking or absorbing light are provided at leastbetween the groups.
 8. The apparatus of claim 1, which further comprisesimage processing electronics, which affect the quality of the displayedimage content, or the quality of the captured images, or both.
 9. Theapparatus of claim 8, wherein the image processing electronics includesmeans for enhancing the displayed image content relative to factors thatincludes; local image non-uniformities, macro-image non-uniformities, orcolor differences, or combinations thereof.
 10. The apparatus of claim8, wherein the image processing electronics includes means for enhancingthe quality of the captured images relative to factors that includes;shadowing, frequency artifacts, spatial non-uniformities, spectraldifferences, or image flicker, or combinations thereof.
 11. Theapparatus of claim 1, wherein the imaging lens provides a Fourier planeand a Fourier plane filter in the Fourier plane.
 12. The apparatus ofclaim 1 wherein the partially transparent pixels are one or more of ared, green, blue, or white pixels.
 13. The apparatus of claim 1 whereinthe partially transparent display pixels are periodically controlled toemit no light.
 14. The apparatus of claim 1, wherein the partiallytransparent display pixels are periodically controlled to be partiallytransparent.
 15. The apparatus of claim 13, further including means forcontrolling the display pixels to provide light to display image contentduring at least a portion of a frame time wherein the partiallytransparent pixels provide image content display light, wherein a frametime is the sum of the time that includes both image capture anddisplay.
 16. The apparatus of claim 15, wherein the control means causesthe display pixels to provide display light to display image contentonly during the portion of a frame time that the partially transparentpixels provide image content display light.
 17. The apparatus of claim1, wherein the capture device captures the scene images only during theportion of the frame time that the partially transparent pixels areoperating to transmit light.
 18. The apparatus of claim 1, wherein theoutput intensity of the display pixels is changed to compensate for theoperation of the partially transparent pixels.
 19. The apparatus ofclaim 1 wherein the display is an emissive display and the image capturedevice receives a portion of light from the emissive display, includesmeans for subtracting such light portion from the scene light from acaptured image.
 20. The apparatus of claim 1 wherein the displayincludes a substrate on which the pixel elements are formed.
 21. Theapparatus of claim 1 wherein the partially transparent pixels furtherinclude at least one transparent thin film electrode structure.
 22. Theapparatus of claim 1 wherein the electronic display is either a liquidcrystal display or an OLED display.
 23. The apparatus of claim 21wherein the partially transparent pixel is a part of a pixel of theliquid crystal display or the OLED display.
 24. The apparatus of claim 1wherein the display is a color display that uses color filters to formcolored pixels.
 25. An integrated imaging apparatus for displayingimages while capturing images of a scene, comprising: a) an electronicdisplay having an array of display pixels which are used to displayimage content; b) at least one image capture device which captures animage, wherein the image capture device comprises at least an imaginglens and an image sensor array; and c) image processing electronics,which enhance the quality of the displayed image content, or the qualityof the captured images, or both; wherein the image capture device looksthrough or is associated with an aperture in the display, the aperturecomprising at least one partially transparent pixel.
 26. The apparatusaccording to claim 24 wherein the image processing electronics controlthe operation of the display pixels or the at least one partiallytransparent pixel, either individually or in combination, to reduce thevisibility of image artifacts for either the displayed image content orthe captured images or both.
 27. The apparatus according to claim 24wherein the partially transparent pixels also provide light to displayimage content.
 28. An integrated imaging apparatus for displaying imageswhile capturing images of a scene, comprising: a) an electronic displayhaving an array of display pixels which are used to display imagecontent; b) the display having at least two apertures integrated withinthe display, wherein each of the apertures comprises a plurality ofpartially transparent pixels; c) at least one image capture device whichcaptures an image, wherein the image capture device comprises at leastan imaging lens and an image sensor array; and d) wherein the imagecapture device looks through an aperture in the display; and wherein thepresence of image artifacts, related to image display and image captureimage is reduced, either individually or in combination, by thepatterning of the plurality of partially transparent pixels within theapertures.
 29. The apparatus according to claim 28 wherein the partiallytransparent pixels also provide light to display image content.
 30. Theapparatus according to claim 28 wherein the plurality of partiallytransparent pixels is patterned, either individually or in clusters, ina quasi-periodic manner, within at least one of the apertures.
 31. Theapparatus according to claim 28, wherein baffles are provided in regionsof the apparatus corresponding to the areas where there are not anyapertures.
 32. The apparatus according to claim 28, wherein baffles areprovided in at least some regions of the apparatus that lack an imagecapture device and the corresponding aperture.